The Interior of Venus

This picture shows a cutaway view of the possible internal structure of Venus. The crust is shown as a dark red, the mantle as a lighter orange-red, and the core yellow.  

Mariner 10 Image of Venus

This image of Venus is a mosaic of three images acquired by the Mariner 10 spacecraft . It shows the thick cloud coverage that prevents optical observation of the surface of Venus. Only through radar mapping is the surface revealed. 

Hemispheric View of Venus

This hemispheric view of Venus, as revealed by more than a decade of radar investigations, is centered at 0 degrees east longitude. The effective resolution of this image is about 3 kilometers. 

Eistla Regio - Rift Valley

A portion of Western Eistla Regio is displayed in this three dimensional perspective view of the surface of Venus. The viewpoint is located 725 kilometers (450 miles) southeast of Gula Mons. A rift valley, shown in the foreground, extends to the base of Gula Mons, a 3 kilometer (1.86 miles) high volcano. This view is facing the northwest with Gula Mons appearing at the right on the horizon. Sif Mons, a volcano with a diameter of 300 kilometers (180 miles) and a height of 2 kilometers (1.2 miles), appears to the left of Gula Mons in the background.

Arachnoids

As the name suggests, arachnoids are circular to ovoid features with concentric rings and a complex network of fractures extending outward. The arachnoids range in size from approximately 50 kilometers (29.9 miles) to 230 kilometers (137.7 miles) in diameter. Arachnoids are similar in form but generally smaller than coronae (circular volcanic structures surrounded by a set of ridges and grooves as well as radial lines). One theory concerning their origin is that they are a precursor to coronae formation. The radar-bright lines extending for many kilometers might have resulted from an upwelling of magma from the interior of the planet which pushed up the surface to form "cracks." Radar-bright lava flows are present in the 1st and 3rd image, also indicative of volcanic activity in this area. Some of the fractures cut across these flows, indicating that the flows occurred before the fractures appeared. Such relations between different structures provide good evidence for relative age dating of events. 

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